(1) Field of the Invention
The present invention relates to an impactor for positioning and holding surgical or veterinary prosthetic implants while they are being driven into position. The present invention has been designed specifically for femoral knee implants, and therefore will be described with particular reference to that application. However, it will be appreciated that the impactor of the present invention could be adapted for use with any surgical or veterinary prosthetic implant which requires driving into position.
(2) Description of Related Art
Any discussion of the prior art is not an admission that such prior art is widely known or forms part of the common general knowledge in the field.
Ideally, an impactor needs to be capable of holding a range of different sizes of implants, and must also be capable of holding each implant in the correct orientation during impact.
Some of the known impactors are designed specifically for a particular design of implant: for example, the impactors disclosed in U.S. Pat. Nos. 5,951,564, 6,063,124 and 5,059,196.
It is a significant advantage if an impactor is easy to manipulate when the implant is being fitted on the impactor, since the implant is sterile and it is important that handling is minimized. However, known designs of impactor typically require very precise, positive adjustment to engage the impactor correctly with the implant, and this is not always easy to achieve under surgical conditions. The impactor disclosed in U.S. Pat. No. 5,417,693 does allow a small amount of play between the impactor and the implant before final clamping, but only in a plane perpendicular to the axis of the impactor.